Explosives have many useful industrial applications. These include surface hardening of austenitic manganese alloy steels, surface deposition coating, welding of metallic components, compression molding of components from powders and granular media, and disposal of unwanted explosive or toxic materials, among others.
The prior art reflects many attempts to contain the explosion process for the suppression of noise, shock and noxious polluting explosion products. Many of these attempts are described in this inventor's prior patents, including U.S. Pat. No. 5,613,453 (now U.S. Pat. No. RE 36,912), which disclosure is incorporated herein by reference.
All of the above-mentioned prior art devices represent improvements over the methods first used for containing explosive detonations, particularly the explosion hardening of manganese steel rail components. This process involves placing an explosive-covered hardenable metal workpiece in an open field, or at the bottom of an open pit such an abandoned gravel pit, and setting off the explosion in the open air, which resulted in objectionable noise, dust, disturbance and contamination of the environment. In addition, the uncontrolled use of explosives in this way required great amounts of space, posed substantial danger to equipment and personnel, and had the undesirable effect of demolishing the ignition leads, the work piece support surface, and virtually everything else within the immediate vicinity of the explosion.
In the United States, the standard railroad track width is 56.5 inches (4′ 8½″) and the largest rail cars commonly used to carry heavy bulky items such as paperboard, lumber and palletized loads commonly have an external width of about 10.5 feet, an external length of about from 55 to 93 feet, and a maximum load capacity of between 70 and 100 tons (140,000 to 200,000 pounds). Loads of up to 42 feet in length are easily accommodated. In special situations, wider load of as much as 12½ feet can also be accommodated. The standard rail section length in the United States is 60 feet (18.3 m). (See: http://www.csx.com/index.cfm/customers/equipment/railroad-equipment/
For highway transport, the United States Department of Transportation has established specific limits for highway trailers of 102 inches wide, 13½ feet high and a gross weight of 80,000 pounds, though in special cases loads of up to 129,000 can be accommodated. Such highway trailers may vary in length of up to 53 feet. However, the rules in individual states may vary, and some may by special permit allow heavier and larger loads. In Europe, truck trailers are generally limited to about 61 feet and 80,000 pounds, although some countries such as Sweden permit larger loads. (See: http://en.wikipedia.org/wiki/Semi-trailer_truck)
As with this inventor's prior patents, it is a principal object of the present invention to provide an improved method and apparatus for containing, controlling and suppressing the effects of explosive detonations used for industrial purposes. The purpose of the invention is to provide a containment device which can contain and suppress each explosion so that it poses no hazard to surrounding plant and equipment, or to the environment.
It is a further object of the invention to provide such a chamber which is of a size and weight which makes it readily transportable by rail, by highway, or both, to its point of eventual use.
A particular design objective is to provide for such a transportable chamber having an empty weight (before the addition of shock-dampening wall filler material) of 110,000 lbs. or less. An alternative object is to provide a method of construction by which the chamber can be manufactured from the assembly by welding of individual prefabricated components.